Pneumatic fuel grader



May 1, 1928. 1,668,218

D. V. SHERBAN PNEUMATIC? FUEL GRADER Filed June 15, 1925 FIELZ.

FIEJ- INVE/VTUR WITNESSES 35 V at/Maw,

tuel delivered.

Fatented May 1, 1928.

DANIEL V. SHERBAN, F CANTON, OHIO,

; insane ern'r orsics- ASSIGNGR TO THE BONNOT COMPANY, 15.

conronarron or onto. 1

PNEUMATIC FUEL GRADER.

Application filed June 15,

This invention relates to the art of grading and separating finely dividedmaterial from that which is less finely divided, and an object oi this invention is to provide a method of and device for grading finely divided material such. as fuel (coal and the like) and for separating the same from less finely divided material.

A further objectof this invention is to produce a pulverized fuel-grading device which may be readily and easily adjusted during operation to vary the fineness oi the A still further object is to produce a finely divided fuel grading device which is cheap to manufacture, of easy installation and Gillcient in operation In the drawings Figure 1 is a view in side elevation of one form of device for'carry ing out this invention. Fig. 2 is a vertical section of the same taken on line 2-2'ot Fig. l and Fig. 3 is an enlarged view of a portion of the device.

The device 1s constructed so as to be inserted in the line leading from the fuel pulverizer to the fuel storage bins or to the point of consumption and is provided with a separating chamber l having an ofi'take 5 in its top and into which two oppositely disposed conduits 6-6 discharge the pulverized coal or other material to be graded.

Chamber 4 on each side of center and below the entrance point for the "fuel for that side is provided with an inclined floor 7 which extends from said fuel entrance point to the top of one side of centrally located hopper 8. The bottom 9' oi: hopper 1 8 as shown by dotted lines Fig. 1 is inclined and leads to an outlet pipe 10 for the coarse rejected fuel. Floors 7-7-, there being one oueach side otthe cl'iamber ot the device,

serve to conduct the coarse fuel deposited; thereon to hopper 8.

extend beneath the entire area of floors 77 which" separate chambers1212 from chamber 4.

Conduits 6-6 communicate with a conduit 1923. Serial No. 645,549;

or pipe 16 which is adapted to convey the and extends from end to end of its chamber; The shafts extend through opposite ends '19l9 of the housing of the device and each shaft at one end is provided with a crank handle 20 by means or which the damper maybe turned to the desired position for controlling the flow of clean air from line 15 through perforations 11 in the inclined supporting floors. I

The entire housing including the ends l919, the sides 21 and top 22 is preterablyv formed from sheet metal. Th-e'top of each side 21 (one marked 23 and the other marked 24) extends into chamber 4: on a radius as shown and since the sheet metal maybe readily bent these ends form adjustable deflectors for directing the fuel laden air streams issuing from conduits 6-6 into chamber tt.

The deflectors are adapted to be adjusted to dillerent positions in order to vary the general direction oi flow of the fuelladen streams of air which enter chamber 4 from opposite sides. Stitlening rod 25 of defied tor 23 by means of a link 27 connects with a belle-rank lever 28 secured to a rod 29 ex tendi'ng-through ends 19 -19 of the housing. Stiltening rod 26 of deflector 24 by means of a link 30 connects with a link 31 loosely car ried on arod 32 mounted in ends 1919 of the housing, A long link 33 connects link 30 to the upper arm of bell crank lever 28. Rod 29 at one end outside ol the housing carries a crank handle 34 and by means of this the position or the deflectors 23 and 24 may be -multaneously adjusted.-

Outlet pipe 10,byn1eansot a suitable pipe line 35, leads the rejected oversized mate rial collected in hopper 8 back to the crusher or to a suitable storage bin. Pipe line 35 is provided with a checkvalve 36 loaded by means of an adjustable weight 37 and by this means the escape of fuel laden air through pipe line 35is prevented.

In the operation of the device ungraded pulverized material is delivered through pipe line or conduit 16 and the air stream carrying the material may be either forced low or induced. The material. of course may be coiulucted either from crushers or pulveriz cers or from any suitable source. The fuel laden air upon entering chamber at is sub jected to a sudden decrease in velocity and change of direction which causes the light particles of fuel to float in the chamber and to b carried through outlet 5 to the point of storage or consumption. The coarse matcrial due to gravity falls onto one or the other of the reticulated inclined members 'lhese reticulated members 7 serve as diffusers for the air entering chamber 4 from chambers l212 in which the air is maintained at a higher pressure than that in chamber l. The coarse material in its travel down theinclined reticulated members to hopper 8 encounters the air streams issuing through the perforations 11 in said member and since these streams issue at an angle to the travel of the material down members 7 a scrubbing action takes place, and the lighter particles of material will be carried by the air issuing through the perforations 11 through chamber l to its outlet. 7

The size of material delivered through outlet 5 will depend upon the air velocities through perforations 11 and the position of deflectors x43 and 2-4 and these air velociA ties can be controlled b y dampers 17 and the position of the deflectors by manipulating crank handle 34. i

The two streams of fuel laden air issu-- through the perforations 11 in the 0p osed members 7 meet at the center of cham- The direction of flow of the streams any smaller particles from the heavier particles deposited thereon and an outlet for graded material. I Y 2. A fuel grader including in combination. an inlet for fuel laden air, a reticuthereforechanged at this point allowing lated surface, means for changing the direction of flow of said fuel laden air so that the heavier particles of fuel in said air are deposited on saic surface, means for directing clean air through said surface so as to separate any smaller particles from the heavier particles deposited thereon and an outlet for air carrying graded material.

3. Ir fuel grader including in combina tiou, an inlet for fuel laden air, an inclined reticulated surface, means for changing the direction of flow of said fuel laden air above said surface so that the heavier par ticles of fuel fall on said surface, means for directing clean air through said surface so as to separate any smaller particles from the heavier aarticles deposited thereon, an outlet for air carrying graded material and an outlet for over-size material.

A fuel grauer including in combina- 'tion, an inlet for fuel. laden air, inclined said fuel laden air so that heavier particles of fuel of predetermined size are deposited on and roll down said inclined plates, means for directing clean air through said plates so as to separate any smaller particles from the heavier particles moving therealong, an outlet for air carrying graded material and an outlet for over-size material below said diffuser plates.

5. The method of grading fuel which consists in changing the direction of flow of a stream of fuel laden air so as to cause the heavier particles of fuel to fall from said stream, and, in scrubbing the fallen particles by a diffused stream of air flowing across the path of said particles.

6. The method of'grading fuel which consists in reducing the velocity and changing the direction of flow of a stream of fuel laden air so as to cause the heavier particlesv of fuel to fall from said stream, directing the fallen particles along an inclined path and in scrubbing the fallen particles and separating therefrom any smaller particles by a stream of air flowing across the path of said particles.

In testimony whereof, I have hereunto subscribed my name this 13th day of June, 1928.

Lfih'l-uli V. SHERBAN. 

